==================================================================
BUG: KCSAN: data-race in complete_signal / do_signal_stop

write to 0xffff8880af3e8064 of 4 bytes by task 12558 on cpu 0:
 freezer_count include/linux/freezer.h:121 [inline]
 freezable_schedule include/linux/freezer.h:173 [inline]
 do_signal_stop+0x562/0x6d0 kernel/signal.c:2395
 get_signal+0x6e4/0x15f0 kernel/signal.c:2717
 arch_do_signal+0x25/0x270 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:161 [inline]
 exit_to_user_mode_prepare+0x124/0x210 kernel/entry/common.c:192
 irqentry_exit_to_user_mode+0x5/0x20 kernel/entry/common.c:280
 irqentry_exit+0xe/0x40 kernel/entry/common.c:368
 sysvec_apic_timer_interrupt+0xc6/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631

read to 0xffff8880af3e8064 of 4 bytes by interrupt on cpu 1:
 wants_signal kernel/signal.c:977 [inline]
 complete_signal+0x7c/0x600 kernel/signal.c:1000
 send_sigqueue+0x25f/0x420 kernel/signal.c:1880
 posix_timer_event kernel/time/posix-timers.c:354 [inline]
 posix_timer_fn+0xe8/0x210 kernel/time/posix-timers.c:380
 __run_hrtimer+0x163/0x460 kernel/time/hrtimer.c:1524
 __hrtimer_run_queues kernel/time/hrtimer.c:1588 [inline]
 hrtimer_interrupt+0x37c/0xa40 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xa3/0x240 arch/x86/kernel/apic/apic.c:1097
 asm_call_irq_on_stack+0xf/0x20
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0x80/0xd0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
 acpi_idle_do_entry+0x94/0x120 drivers/acpi/processor_idle.c:517
 acpi_idle_enter+0x22e/0x260 drivers/acpi/processor_idle.c:648
 cpuidle_enter_state+0x2a5/0x7e0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:132 [inline]
 cpuidle_idle_call kernel/sched/idle.c:213 [inline]
 do_idle+0x1e7/0x2c0 kernel/sched/idle.c:273
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
 secondary_startup_64_no_verify+0xa6/0xab

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================